Demonstration of amyloid in murine and human secondary amyloidosis by the immunoperoxidase technique.

A specific rabbit anti-murine amyloid A protein (anti-AA) has been used in the immunoperoxidase (IP) technique for the detection of amyloid in formalin-fixed, paraffin-embedded, tissue obtained from amyloidotic mice and a post-mortem kidney specimen from a patient with amyloidosis secondary to osteomyelitis. Amyloidosis was induced in five out of 20 white mice by weekly intraperitoneal injections of complete Freund's adjuvant. Amyloid deposits were clearly demonstrated both by the Congo Red and by the IP techniques. The antibody against murine AA was found to be cross-reactive with human AA. These preliminary results suggest that the IP technique with the use of specific antibodies against the different amyloid proteins might be extremely useful for the histological dianosis and classification of amyloidosis.